Construction and testing of self-drilled soil nails

Current standards and best practice guidance recognise that testing of self-drilled hollow bar soil nails can be problematic as conventional packers and debonded lengths cannot be constructed. As a result, this causes difficulty in testing and confirming the ultimate bond resistance within the passive zone of a soil-nailed slope, and thus the design soil nail lengths. This paper provides a summary and review of the various testing procedures adopted for a soil nail construction project in Scotland. The practical design considerations, and their validation through the installation and testing of 49 sacrificial test nails, are detailed. The construction issues associated with the nail installation and testing are also outlined and discussed in light of the results obtained using different testing approaches. The aim of this case study is to report on the experiences with installation and testing of hollow bar soil nails. The objectives are to develop an initial data base of available soil–grout bond strength of hollow bar soil nails based on the several practical installation procedures used in this project and to establish areas for improvement of installation, testing and quality control in order to perform comparable pullout tests on self-drilled hollow bar soil nails. </jats:p

Oblique surface waves at an interface of metal-dielectric superlattice and isotropic dielectric

We investigate the existence and the dispersion characteristics of surface waves that propagate at an interface between metal-dielectric superlattice and isotropic dielectric. Within the long wavelength limit, when the effective-medium approximation is valid, the superlattice behaves like a uniaxial plasmonic crystal with the main optical axes perpendicular to the metal-dielectric interfaces. We demonstrate that if such a semi-infinite plasmonic crystal is cut normally to the layer interfaces and brought into the contact with semi-infinite dielectric, a new type of surface modes can appear. The propagation of such modes obliquely to the optical axes occurs under favorable conditions that regard thicknesses of the layers, as well as the proper choice of dielectric permittivity of the constituent materials. We show that losses within the metallic layers can be substantially reduced by making the layers sufficiently thin. At the same time, a dramatic enlargement of the range of angles for oblique propagation of the new surface modes is observed. This can lead, however, to the field non-locality and consequently to the failure of the effective-medium approximation.Comment: 4 pages, 3 figure

Scaling of Hamiltonian walks on fractal lattices

We investigate asymptotical behavior of numbers of long Hamiltonian walks (HWs), i.e. self-avoiding random walks that visit every site of a lattice, on various fractal lattices. By applying an exact recursive technique we obtain scaling forms for open HWs on 3-simplex lattice, Sierpinski gasket, and their generalizations: Given-Mandelbrot (GM), modified Sierpinski gasket (MSG) and n-simplex fractal families. For GM, MSG and n-simplex lattices with odd values of n, number of open HWs $Z_N$, for the lattice with $N\gg 1$ sites, varies as $\omega^N N^\gamma$. We explicitly calculate exponent $\gamma$ for several members of GM and MSG families, as well as for n-simplices with n=3,5, and 7. For n-simplex fractals with even n we find different scaling form: $Z_N\sim \omega^N \mu^{N^{1/d_f}}$, where $d_f$ is fractal dimension of the lattice, which also differs from the formula expected for homogeneous lattices. We discuss possible implications of our results on studies of real compact polymers.Comment: 19 pages, 13 figures, RevTex4; extended Introduction, several references added; one figure added in section II; corrected typos; version accepted for publication in Phys.Rev.

Large Square Bale Biomass Transportation Analysis

Transportation logistics are a critical factor in the optimization of biomass supply chains. A single 25 million gallon per year cellulosic ethanol biorefinery will require 18,500 semi loads of bales to be delivered to the plant. For a typical corn stover biomass supply chain, baled corn stover must be transported in two phases. The first phase is from the field to a storage site while the second is from the storage site to the biorefinery. All activities in-between these two points are connected and together they form the biomass supply chain. The goal of supply chain optimization is to minimize the total cost of these activities (transportation cost per unit, inventory cost per unit etc.) while satisfying the supply demands of a biorefinery. This paper will report on a recent analysis of production scale biomass transportation. Intensive GIS tracking and videocapture of the loading, securement, hauling, and unloading events of industrially produced large square bales of corn stover were collected and results were summarized. Specific results including; metrics for measuring supply chain efficiency, current capability of biomass supply chains, and sensitivity analysis to improvements in future supply chains will be presented. The outcomes of this work will help in forming more efficient biofuel production process and improve biofuel life cycle as well

KRVNI OPTOK SREDNJE MOŽDANE ARTERIJE U PRETKAZIVANJU NEPOVOLJNA ISHODA U FETUSA S USPORENIM RASTOM

The development of a Doppler ultrasound technique offers new opportunities in the follow-up of the mater-nal and fetal circulation in the normal and in the high-risk pregnancies. Analysis of sonograms (Doppler velocity wave-form) on the a.cerebri media (ACM) gives important information about the status and the condition of the fetus. The resistance index (RI) has a significant application in the clinical practice for the detection and follow-up of the fetal growth and the perinatal outcome at the IUGR fetus. Material and methods. The Doppler ultrasound (US) follow-up was perfor-med in 86 normal pregnancies and 78 pregnancies with an IUGR of the fetus within the third trimester, divided in seven groups of gestational weeks (g.w.) With the Doppler machine TOSHIBA SONOLAYER SSA 120A and the application of an 3.75 MHz transabdominal probe, RI was determined at the a.cerebri media ( RIACM). Results. The analysis of the RIACM in normal pregnancies showed that the distribution was regular in the followed-up gestational weeks which manifested as a permanent decrease of the values for RIACM (of 0.83 in the 28–29 g.w.; 0.77 in the 34 –35 g.w., up to 0.725 at the term). In the pregnancies with an IUGR of the fetus, the RIACM was measured, which for any group of a g.w. statistically was significantly different from the findings in the normal pregnancies (p48 h (p48h; perinatalnim mortalitetom (p<0.001). U predviđanju lošeg peri-natalnog ishoda, u kojemu su uključeni svi prije analizirani parametri, RI a. cerebri medije je predviđao loš perinatalni ishod sa senzitivnošću od 68,9%, specifičnošću od 77%, PPV od 79% i NPV od 69,4%. Zaključak. RI a.cerebri medije je važan parametar za predviđanje perinatalnog ishoda u kliničkoj praksi. Usprkos brojnim rezultatima koji promiču dopler ultrazvuk za najranije predviđanje fetalne patnje od CTG-a, najbolji rezultati se dobivaju zajedničkom primjenom ove dvije kao i nekoliko drugih antepartalnih metoda i analiza. Dopler ultrazvučna analiza pokazuje kronične promjene koje same po sebi ne ukazuju na potrebu momentalnog prekida trudnoće, sve dok se CTG-om ne utvrde akutne promjene. Ove dvije metode ne isključuju jedna drugu već se dopunjuju

Temperature non-uniformity due to heat conduction and radiation in the pulse calorimetry technique

The paper presents an assessment of the unwanted temperature non-uniformity found in high temperature applications of the pulse calorimetry technique. Specimens in the form of a solid cylinder undergoes fast electrical heating and an intense heat radiation at high temperatures, coupled with the heat conduction the specimens’ cold ends, make them having a highly non-uniform temperature distribution, both in their radial and axial directions. By using finite element method simulations of a typical pulse calorimetry experiment, the temperature non-uniformity across the specimen diameter and along the specimen effective length has been estimated for different specimen dimensions and materials, as well as for different heating rates. The obtained results suggest that an optimization of experimental parameters, such as the specimen diameter, specimen total and effective length and heating rate, is needed for minimization of the temperature non-uniformity effect

Analysis of the evaporative towers cooling system of a coal-fired power plant

The paper presents a theoretical analysis of the cooling system of a 110 MW coal-fired power plant located in central Serbia, where eight evaporative towers cool down the plant. An updated research on the evaporative tower cooling system has been carried out to show the theoretical analysis of the tower heat and mass balance, taking into account the sensible and latent heat exchanged during the processes which occur inside these towers. Power plants which are using wet cooling towers for cooling condenser cooling water have higher design temperature of cooling water, thus the designed condensing pressure is higher compared to plants with a once-through cooling system. Daily and seasonal changes further deteriorate energy efficiency of these plants, so it can be concluded that these plants have up to 5% less efficiency compared to systems with once-through cooling. The whole analysis permitted to evaluate the optimal conditions, as far as the operation of the towers is concerned, and to suggest an improvement of the plant. Since plant energy efficiency improvement has become a quite common issue today, the evaluation of the cooling system operation was conducted under the hypothesis of an increase in the plant overall energy efficiency due to low cost improvement in cooling tower system

Use of an Integrated System Dynamics Model for Analyzing Behaviour of the Social-economic-climatic System in Policy Development

Climate change remains one of the most critical issues that humans and the natural world face today. Yet while a strong body of scientific research has identified the risks if mitigation and adaptation measures are not taken, there still remains a policy lag. This leads researchers to pose several questions: is there an identified need by the policy domain for more or different science? Is the science that is conducted made policyrelevant? If not, are there tools to better link science to policy? This report will explain the process of science-policy communication related to the development of an integrated system dynamics model of the social-economic-climatic system at the University of Western Ontario under NSERC strategic grant program funding. It will describe the science-policy interface and outline the main challenge to developing science tools for policy, and will then explain how the UWO research team overcame such challenges. Finally, it explains (a) briefly the proposed model and (b) the process of policy scenarios development. The main objective of the research presented in this report is to bring the model closer to policy makers and emphasize how useful this tool is specifically for the Canadian federal government. The science policy communication process has been established through the set of interviews and workshops. Interviews were used (a) to identify the issues of importance to be incorporated in the model development and (b) to formalize a set of policy scenarios that will provide input for policy making. Workshops were used to communicate science to policy developers and discuss the issues of importance for policy development. The research was fundamentally based on a multi-disciplinary approach that assisted in bridging the research domain to the policy domain. Ultimately, the feedback from the interviews and workshops was embedded in the development of the model and its scenarios, and made it possible to transform policy questions into model scenarios. In other words, by linking science and policy domains, the research team was able to produce a science-based and policy-relevant tool. Limitations to the work mainly reflect the current stage of research and model development. As the strategic research continues on the integrated system dynamics model of the social-economic-climatic system, these limitations are likely to be overcome. The other key limitation is in the selection of the government partners. While the current group of partners has provided valuable insight, further research will aim to expand the group of partners across different departments. This will not only reflect a broader range of interests, but will also more accurately represent a systems view of government. Furthermore, a broader range of disciplinary biases will be consulted, including government policymakers who work more intimately with science and policy research.https://ir.lib.uwo.ca/wrrr/1029/thumbnail.jp

Review of Mammarenavirus Biology and Replication

The family Arenaviridae is divided into three genera: Mammarenavirus, Reptarenavirus, and Hartmanivirus. The Mammarenaviruses contain viruses responsible for causing human hemorrhagic fever diseases including New World viruses Junin, Machupo, Guanarito, Sabia, and Chapare virus and Old World viruses Lassa, and Lujo virus. These two groups of arenaviruses share the same genome organization composed of two ambisense RNA segments. These segments contain four open reading frames that encode for four proteins: the nucleoprotein, glycoprotein precursor, L protein, and Z. Despite their genome similarities, these groups exhibit marked differences in their replication life cycles. This includes differences in attachment, entry, and immune evasion. By understanding the intricacy of replication in each of these viral species we can work to develop counter measures against human diseases. This includes the development of vaccines and antivirals for these emerging viral threats. Currently only the vaccine against Junin virus, Candid#1, is in use as well as Ribavirin for treatment of Lassa Fever. In addition, small molecule inhibitors can be developed to target various aspects of the virus life cycle. In these ways an understanding of the arenavirus replication cycle can be used to alleviate the mortality and morbidity of these infections worldwide

Pojava stres sindroma (PSS) i mutacije na genu za rijanodin receptor (RYR1) kod evropske divlje svinje Sus scrota ferus

Expression of the stress syndrome (PSS) in European wild pig was evaluated by Halothane test and tested animals were typed by PCR/RFLP test for C/T mutation at nt 1843 in RYR1 gene. A total of 56 animals, at the age of 5 months, weighing 20 kg average, were tested. Hal+ (MHS - malignant hyperthermia susceptible) phenotype was revealed in 6 pigs, 47 animals expressed Hal- (MHN - malignant hypedhermia resistant) phenotype, while 3 animals showed no response to administration of 3% halothane after 5 minutes and they were marked as Hair (halothane resistant) phenotypes. Genotyping of 56 wild pigs revealed that the tested population was homozygous for the normal C/C allele at RYR1 locus. The results obtained by halothane test show that expression of the PSS in wild pigs is modulated and influenced by factors other then RYR1 genotype.Pojava stres sindroma kod evropske divlje svinje ispitivana je primenom halotan testa i izvršena je genotipizacija na poziciji nukleotida 1843 u genu za rijanodin receptor (RYR1) korišćenjem PCR/restriktivnog endonukleaza testa. Testirano je ukupno 56 životinja, starosti 5 meseci i prosečne telesne mase od 20 kg. Od ukupno 56 jedinki 6 životinja je pokazalo Hal+ (MHS) fenotip, 47 jedinki je imalo Hal+ (MHN) fenotip, a tri jedinke nisu uopšte reagovale na 3% halotan ni posle 5 minuta uvođenja u narkozu i one su označene kao Hair fenotip. Genotipizacija na poziciji nukleotida 1843 u genu za rijanodin receptor pokazala je da su sve ispitivane jedinke, bez obzira na halotan status imale normalan RYR1 C/C genotip. Dobijeni rezultati ukazuju da se stres sindrom javlja i kod divljih svinja, mada postoji značajna modulacija pune ekspresije sindroma drugim faktorima